There is a secret in this game, and here's how to get it: After you beat DJ Octavio and after the room where you get the ceiling cat, the room next to the 6 gate has some electric wires, and one of them isn't moving. That's intentional, because you can fall through it to a maze in which you have to go to the left to find a blue room. You need the ninth key to open the gate and the helikitty that flies up. You need to pass through the electricity that isn't moving, which is harder than it seems. The hardest part is the enterance. You need to die to get invincibility frames to go in the lightning and try to get helikitty up, once you do it's not THAT hard. With the enterance just keep comitting suicide until you pull it off. UF you succeed, you're awarded with the Sekrit Item of Wonder. It does absolutely nothing in-game, just gives you an achievent. I hope this helped you with the secret!
There arent any technical problems in this game for me, so i dunno why everyone says its laggy. But still, this is a very old game so please understand that.